1. Field of the Invention
The present invention relates to a technical field of a display, more particularly, relates to a device for recording a holographic 3D image, a device for reproducing a holographic 3D image, a method for recording a holographic 3D image, and a method for reproducing a holographic 3D image.
2. Description of the Related Art
In a linear optical material, such as lens, prism, etc., a light beam may pass through the linear optical material and cannot change an inherent property of the linear optical material. A light induced refractive index change effect, often simply called as a photorefractive effect, is referred to an effect that an electric charge field is induced due to a photoelectric effect when an optical material is irradiated by light and a refractive index of the optical material is changed with a spatial intensity distribution of light under the photoelectric effect. However, the photorefractive effect generally is not limited to the light induced refractive index change. Since the optical property of the optical material having the photorefractive effect can be changed by the light passing through the optical material, the optical material is a non-linear optical material. On one hand, such optical material has photorefractive crystals that can record a complicated optical image like a conventional film sensitizer used in a camera. On the other hand, such optical material having the photorefractive effect can be reused because the image recorded on the optical material can be removed, while the conventional film cannot be reused after exposed because the image recorded on the film cannot be removed, therefore, such optical material is superior to the film. One of important advantages of the photorefractive crystal is that the photorefractive crystal can store about 5000 different images in a volume of about 3 cm3 and can rapidly display any one of the images.
A holography of light wave comprises all information of it, including vibration amplitude and phase information. A normal photography only can record the intensity information (vibration amplitude information) of the light wave and omit the phase information of the light wave. The holography can record all information (vibration amplitude and phase information) of an original object light wave in a record medium based on interference principle. Furthermore, when the record medium is illuminated by a reproduction light wave, the original object light wave can be reproduced based on diffraction principle, achieving the reproduction of a vivid 3D image.
Since the 3D effect of the image reproduced by the holography is very strong, the 3D display technology based on the holography is becoming popular. The holography 3D display technology mainly comprises synthetic holography 3D display, digital holography 3D display and erasable material-based holography 3D display.